After his girlfriend falls ill, Cole Blaquesmith seeks out the aid of crazed witch doctor Mortimer Absinthe in search for a cure. When Cole is betrayed and retaliates, he enters a coma and awakens 100 years in the future where Absinthe now rules with an iron fist as Cole learns that he is the only one who can end his reign.
- Julian Dennison as Cole Blaquesmith
- Hugo Weaving as Dr. Mortimer Absinthe
- Stephen Blackehart as Faust
- Emilia Clarke as Victoria
- To-be-confirmed actor as Rutherford Nixon
- To-be-confirmed actor as Sir Robert Peel
- To-be-confirmed actress as Fiona
- To-be-confirmed actor as Hiram Sundown
- To-be-confirmed actor as Milton Sundown
- To-be-confirmed actress as Tini Sundown
- Louis Ashbourne Serkis as Laslo
- To-be-confirmed actor as Randy
- To-be-confirmed actor as Sköm
- To-be-confirmed actor as Rikk (flashback only)
- Despite being the closest adaptation to the source material than other films, Steampunk still varies slightly from the original comics with a few examples:
- The film is set mainly in 1954 while a prologue took place in 1854. In the comics, the prologue took place in the 18th century, not 17th and Cole briefly visited 1954 instead.
- The film features Fiona as a young mill worker who is poisoned by Absinthe, but the comics depict her as a teacher of the lower class who falls ill after her school is burned down.
- Characters from the comics not present in the film include; Batcat, D. Danforth, Napoleon Bonaparte, Iron Monk, Medik, Mambutu X and the Pestilent Brothel.
- Of these, D. Danforth, Napolean Bonaparte, and Mambutu X are introduced in future installments.